1. Field of the Invention
The present invention relates to a paper sheet detection apparatus which detects the magnetic ink printed on paper sheets such as securities.
2. Description of the Related Art
One type of paper sheet detection apparatus detects a paper sheet by holding and conveying it to a detection sensor by a conveying belt, for example, or by holding and conveying a paper sheet to a detection sensor by a pair of conveying rollers.
Another type of paper sheet detection apparatus detects a paper sheet by placing a paper sheet on a conveying belt with holes and conveying it to a suction chamber. A paper sheet conveyed to a suction chamber is sucked onto a conveying belt by sucking out air through the holes in the conveying belt, and the whole non-sucked side of the sucked paper sheet is detected.
However, in the prior art, a paper sheet flaps or bends due to the vibration of a conveying belt or the fluctuation in the speed of a pair of conveying rollers, and such flapping and bending are mixed into the detection signal of a detection sensor as a noise, degrading the detection accuracy.
The present invention has been made taking notice of the above-mentioned circumstances. It is an object of the present invention to provide a paper sheet detection apparatus, which prevents flapping and bending of a paper sheet and obtain an accurate detection signal of a detection device.